In terms ok XKB, I would put it this way: If shortcut is Ctrl-a - walk across all keys defined in the current configuration. If for some key the keysym is "a" in ANY group - listen to Ctrl-<keycode>, ignoring the group.
In terms ok XKB, I would put it this way:
If shortcut is Ctrl-a - walk across all keys defined in the current configuration. If for some key the keysym is "a" in ANY group - listen to Ctrl-<keycode>, ignoring the group.